Connection recovery: remove recorded bindings of auto-delete entities

The same way Java client does it [1][2][3].

Fixes #1905.

1. https://github.com/rabbitmq/rabbitmq-java-client/blob/main/src/main/java/com/rabbitmq/client/impl/recovery/AutorecoveringChannel.java#L913-L919
2. https://github.com/rabbitmq/rabbitmq-java-client/blob/main/src/main/java/com/rabbitmq/client/impl/recovery/AutorecoveringConnection.java#L1118-L1131
3. https://github.com/rabbitmq/rabbitmq-java-client/blob/main/src/main/java/com/rabbitmq/client/impl/recovery/AutorecoveringConnection.java#L1063-L1069

Author: michaelklishin

projects/RabbitMQ.Client/Impl/AutorecoveringConnection.Recording.cs

@@ -265,6 +265,8 @@ await DeleteAutoDeleteExchangeAsync(binding.Source,
 
         }
 
+        internal int RecordedBindingsCount => _recordedBindings.Count;
+
         internal async ValueTask RecordBindingAsync(RecordedBinding binding,
             bool recordedEntitiesSemaphoreHeld)
         {
@@ -419,6 +421,15 @@ private void DeleteAutoDeleteQueue(string queue)
                 if (!AnyConsumersOnQueue(queue))
                 {
                     _recordedQueues.Remove(queue);
+                    // remove bindings targeting this queue; also cascade to auto-delete exchanges
+                    foreach (RecordedBinding binding in _recordedBindings.ToArray())
+                    {
+                        if (binding.Destination == queue)
+                        {
+                            DoDeleteRecordedBinding(binding);
+                            DoDeleteAutoDeleteExchange(binding.Source);
+                        }
+                    }
                 }
             }
         }

projects/Test/Integration/ConnectionRecovery/TestRecoveryWithDeletedEntities.cs

@@ -31,7 +31,9 @@
 
 using System.Threading.Tasks;
 using RabbitMQ.Client;
+using RabbitMQ.Client.Events;
 using RabbitMQ.Client.Exceptions;
+using RabbitMQ.Client.Framing;
 using Xunit;
 using Xunit.Abstractions;
 
@@ -150,5 +152,72 @@ public async Task TestThatDeletedQueuesDontReappearOnRecovery()
                 AssertShutdownError(e.ShutdownReason, 404);
             }
         }
+
+        [Fact]
+        public async Task TestAutoDeleteQueueBindingsRemovedWhenConsumerCancelled()
+        {
+            // See rabbitmq/rabbitmq-dotnet-client#1905.
+            //
+            // When the last consumer on an auto-delete queue is cancelled, the queue
+            // and its bindings must be removed from recorded topology so that recovery
+            // does not try to restore them.
+            string exchangeName = GenerateExchangeName();
+            await _channel.ExchangeDeclareAsync(exchangeName, ExchangeType.Direct, autoDelete: true);
+
+            var queueDeclareOk = await _channel.QueueDeclareAsync("", false, false, autoDelete: true);
+            string queueName = queueDeclareOk.QueueName;
+            await _channel.QueueBindAsync(queueName, exchangeName, routingKey: "key");
+
+            var autorecoveringConn = (AutorecoveringConnection)_conn;
+            Assert.Equal(1, autorecoveringConn.RecordedExchangesCount);
+            Assert.Equal(1, autorecoveringConn.RecordedQueuesCount);
+            Assert.Equal(1, autorecoveringConn.RecordedBindingsCount);
+
+            var consumer = new AsyncEventingBasicConsumer(_channel);
+            string consumerTag = await _channel.BasicConsumeAsync(queueName, true, consumer);
+            await _channel.BasicCancelAsync(consumerTag);
+
+            Assert.Equal(0, autorecoveringConn.RecordedExchangesCount);
+            Assert.Equal(0, autorecoveringConn.RecordedQueuesCount);
+            Assert.Equal(0, autorecoveringConn.RecordedBindingsCount);
+
+            await CloseAndWaitForRecoveryAsync();
+            Assert.True(_channel.IsOpen);
+        }
+
+        [Fact]
+        public async Task TestAutoDeleteQueueBindingsRemovedWhenChannelClosed()
+        {
+            // See rabbitmq/rabbitmq-dotnet-client#1905.
+            //
+            // Same as above but uses channel closure as the trigger.
+            string exchangeName = GenerateExchangeName();
+            var autorecoveringConn = (AutorecoveringConnection)_conn;
+
+            IChannel ch = await _conn.CreateChannelAsync(_createChannelOptions);
+            await using (ch.ConfigureAwait(false))
+            {
+                await ch.ExchangeDeclareAsync(exchangeName, ExchangeType.Direct, autoDelete: true);
+
+                var queueDeclareOk = await ch.QueueDeclareAsync("", false, false, autoDelete: true);
+                string queueName = queueDeclareOk.QueueName;
+                await ch.QueueBindAsync(queueName, exchangeName, routingKey: "key");
+
+                Assert.Equal(1, autorecoveringConn.RecordedExchangesCount);
+                Assert.Equal(1, autorecoveringConn.RecordedQueuesCount);
+                Assert.Equal(1, autorecoveringConn.RecordedBindingsCount);
+
+                var consumer = new AsyncEventingBasicConsumer(ch);
+                await ch.BasicConsumeAsync(queueName, true, consumer);
+                await ch.CloseAsync();
+            }
+
+            Assert.Equal(0, autorecoveringConn.RecordedExchangesCount);
+            Assert.Equal(0, autorecoveringConn.RecordedQueuesCount);
+            Assert.Equal(0, autorecoveringConn.RecordedBindingsCount);
+
+            await CloseAndWaitForRecoveryAsync();
+            Assert.True(_channel.IsOpen);
+        }
     }
 }